is it usual for an eight month ball python to go off feed,her temps are spot on
Make sure your temperatures 80-84 on the cool side, 90-94 on the warm side (Digital thermometer at the bottom of the enclosure is needed for accurate temperature measurements)
your humidity is 50%-60% the hides are tight enough and all sides are touching your bp's body (Avoid log hide) the enclosure is in a low traffic area and is not too big
If you handle your BP a lot stop until he resume feeding Try to add crumble newspaper for added security.
BP also fast to catch up, feed a small prey once a week for more consistency in feeding.